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Vanilla 2.6 is here! It includes security fixes and requires PHP 7.0. We have therefore ALSO released Vanilla 2.5.2 with security patches if you are still on PHP 5.6 to give you additional time to upgrade.

It's unlikely that there will be another 2.3.x release so changing the link in the 2.3 branch on GitHub wouldn't make sense.

The way captchas are implemented in Vanilla 2.4 has been changed drastically. Until then, recaptcha was part of the dashboard application, which handles everything user related in Vanilla.
With Vanilla 2.4 there comes a captcha core class which can be extended by plugins and that's what happend to recaptcha: it has been made a plugin. In that plugin, the link has been fixed

Attempt to setup a new vanilla forum with 2.3.1. The first think you're going to want to do is to enable Captcha (not only because that's just a good idea, but also because the default registration page points out that captcha ISN'T yet setup). Oh, and the second thing you're going to want to do is enable Google OAuth signin - and that plugin is broken by default, too (but that's another story/thread).

So: follow the directions and BOOM, 404 error.

Yes, vanilla is in use all over the place, but you're got going to be adding many NEW forums when your default 'getting started' experience ends in a 404.

@Jeff_s Good day Vanilla is a safe forum, I do not understand pq says that captcha does not work for me it works with recaptcha, I have a forum with 500 users and more than 150K visits in a month ranged very well alexa, and works perfect, you will not find a free forum with the support and benefits of vanilla,